CUC for reef tank. Help with algae.

So I have a 120 gallon reef tank, and I am looking for a clean up crew to help me a little with my algae. I know that they won't fix the problem completely, but at least they would help. I have a good amount of algae. Everyday I scrub and the next day it is almost exactly how it was the day before. This happened because I was changing the sand one day and since then algae has just exploded in my tank. Its on the glass, sand, and even the rocks a little bit. Its such a pain in the butt to see all this algae every where because its an eyesore! Anyway, in my quest to fix my problem I think a clean up crew would be good. As said, I know it won't fix the problem, but it can't hurt. I currently have a serpent star, sandsifting star, a few hermits, and a small amount of snails.



1. How much of a clean up crew do I need for my 120?

2. What would you recommend? Snails? Urchins? Cucumbers?



I would like a few critters for each level (sand, rocks, glass). I don't want any hermits, I have had bad experiences with them and they eat my snails. Also I don't want crabs. Thanks!